1. Technical Field
The present invention relates in general to an improved performance of a wireless access in Internet Protocol (IP) network, and in particular to a method and system to manage the end-to-end QoS on an IP network utilizing wireless access. Still more particularly, the present invention relates to a method and system to provide a wireless QoS agent for an all-IP network.
2. Description of the Related Art
Wireless access is expected to be one of the key access technologies for providing IP services to the user, end-to-end seamlessly. The-wireless network works as the access subnet of the IP network, has its own unique set of complex characteristics. To improve the behavior of the wireless link""s susceptiblely to frequent error bursts (due to fading, shadowing etc.), the usage of various low layer (physical/link) techniques such as Forward Error Correction (FEC) coding, interleaving, dynamic channel allocation, power control, link layer Automatic Request for Retransmission (ARQ) mechanisms, etc. becomes necessary to provide the required end-to-end performance to the user over an all-IP network.
Traditional Internet is based on a stateless switching fabric and supports only xe2x80x9cbest effortxe2x80x9d packet data services. With the proliferation of multimedia services via the Internet-video-conferencing, tele-medicine, telephony, video-on-demand etc., there is an increasing demand to support guaranteed Quality-of-Service (QoS) over the Internet. In IP based networks, the performance is characterized by the speed and fidelity of the data transferred from source to destination. The term for characterizing a performance of an IP packet flow is xe2x80x9cQuality of Servicexe2x80x9d (QoS) and is measured by packet transfer delay, jitter, probability of packet loss and throughput. There are two other forms utilized to define the performance of a system, namely, grade of service (GOS) and availability and reliability. Under the xe2x80x9cIP QoSxe2x80x9d umbrella, two solutions work towards the development of a framework to support QoS in IP best-effort networks. Work of the Integrated Services (Int-Serv) working group led to the development of the Integrated Services Architecture and the RSVP signaling protocol. RSVP promises per-flow QoS through resource reservation and maintenance of xe2x80x9csoft statexe2x80x9d in all intermediate routers. Int-Serv has limitations on four major areas namely (a) scalability, (b) overhead is too large, (c) this is a connection-oriented approach and, (d) most of the Host to Host connections do not address the intermediate management point issues. To overcome these limitations, the Differentiated Services (Diff-Serv) architecture was proposed. The Diff-Serv architecture aims to provide scalable service discrimination and xe2x80x9cbetter than best effortxe2x80x9d service in the Internet without the need of per-flow state maintenance at every router.
Over the last few years, there has been an explosive growth of wireless communication technology. Voice communication over wireless links utilizing cellular phones has matured and alongside portable computing devices such as notebook computers and personal digital assistants (PDAs) have emerged resulting in such applications as electronic mail and calendar/diary programs being provided to mobile or roving users. Observing this trend, it can be predicted that the next generation traffic in wireless networks will be mostly generated by personal multimedia applications including fax, video-on-demand, news-on-demand, World Wide Web (WWW) browsing, and traveler information services.
The current circuit switched based wireless networking is not efficient and cost effective. Moreover, in the current solution, overlay data network is needed to support data services and multimedia service implementation is complex. As the communications market is being driven by the demand for sustained connectivity to the Internet, it has become attractive to merge the wireless network with the Internet. The ability to provide seamless roaming and cost-effective connectivity to the network from anywhere and anytime will be an extra value from the network operators. Data services will seek to achieve an optimal combination of wide area network mobility and various types of multimedia service guarantees, making use of the already existing Internet infrastructure.
Wireline networks seldom lose packets due to link failure, which is generally caused by node congestion because of excess traffic. Hence, if suitable flow control and traffic shaping is applied at the edge of the network, the loss behavior can be controlled. The same premise applies for controlling delay and jitter within the network. The wireless link, on the other hand, demonstrates totally unpredictable behavior (fading, shadowing etc.) largely due to the mobility of the users, the terrain conditions, and multipath effects, etc. The reliability of the CDMA wireless link is also heavily dependent on the other-user interference which is a random function of the number and spatial co-location of the users.
Notwithstanding the hostile nature of the radio link and limited QoS provisioning-within the Internet, the next generation wireless networks aim at providing the end user with a multitude of services comparable in quality to their wire-line counterpart. Present QoS provisioning techniques within the Internet are not enough for quality assurance in the wireless subnet, primarily because of the unpredictable nature of the radio link. QoS management for wireless links will involve coordination among many different lower layer techniques which may require frequent link adaptability and dynamic adjustments, necessitating a control agent.
Therefore, a need exists for a wireless QoS agent/manager responsible for mapping multimedia IP QoS requirements to radio link specific requirements, providing dynamic link adaptability and resource allocation capabilities, low layer flow control, air link QoS monitoring, and providing seamless extension of IP QoS to the mobile user. The present invention solves this problem in a new and unique manner that has not been part of the art previously.
It is therefore one object of the present invention to provide an improved performance of a wireless access in IP network.
It is another object of the present invention to provide a mechanism to manage the end-to-end QoS on an IP network utilizing wireless access.
It is another object of the present invention to provide a wireless QoS agent for an all-IP network.
The foregoing objects are achieved as is now described. A wireless quality of service (QoS) agent for an all-Internet Protocol (IP) network is disclosed. The QoS agent couples to an all-IP network. The coupling means includes communication means for transfer of information between the agent and a QoS manager of the all-IP network. The agent is also able to seamlessly extend QoS support for multimedia applications from wireline to wireless and control QoS of the multimedia applications sent over wireless connections on the all-IP network.
The above as well as additional objects, features, and advantages of the present invention will become apparent in the following detailed written description.